1. Field of the Invention
The present invention relates to a slit camera apparatus for use as an apparatus for indicating the order of arrival of competitors at a goal, for example.
2. Description of the Prior Art
Slit cameras are heretofore used as apparatus for indicating the order of arrival of competitors at a goal. For example, in a horse race track, a slit camera having a slit extending parallel to a goal post is used to determine the order of the horses that arrive at the goal, in the event that the order cannot be judged directly by eyes.
Conventional slit cameras include a photographic slit camera employing a silver halide film and a slit camera apparatus including a line sensor as disclosed in Japanese laid-open patent publication No. 2-84977.
The slit camera apparatus disclosed in the above publication comprises a slit camera employing a line sensor and an endless electronic display board. The slit camera is fixed in position such that its slit extends in a direction perpendicular to the direction (plane) in which subjects move, and the direction of the slit coincides with the longitudinal direction of the line sensor. The direction of the slit is perpendicular to the transverse direction of the line sensor.
In use, data produced by the line sensor and the display position on the electronic display board are synchronized with each other for displaying the order of arrival of the moving subjects at the goal on the electronic display board.
Slit camera apparatus as apparatus for indicating the order of arrival of competitors or moving subjects at a goal require that the order of arrival of the moving subjects be accurately determined based on the displayed images of the moving subjects, and also that the displayed images be accompanied by time information indicating the times at which the moving objects are photographed by the slit camera. To meet the above requirements, it is necessary to store, in a memory, image information of areas where the objects pass through the goal and also time information corresponding to the image information.
The amount of image information that can be stored in a memory is determined by the storage capacity of the memory. Generally, the cost and other factors of the memory prevent a large amount of image information, i.e., image information spanning a long period of time, from being stored in the memory.